Track grinding brick and adapter



Sept. 21, 1937. I T LARSSQN 2,093,969

TRACK GRINDING BRICK AND ADAPTER Filed Aug. 9, 1955 42 E 3/ /z9 57 3a THLIRE LARSSCIN 34 F/QZ v 34 F/GG low cost.

Patented Sept. 21, 1937 UNITED STATES PATENT OFFICE Thur-e Larsson, Worcester, Mass., assignor to Norton Company, Worcester, Mass, a corporation of Massachusetts Application August 9,

2 Claims.

The invention relates to reciprocating grinders, and with regard to its more specific features to a track grinding brick and an adapter therefor.

One object of the invention is to provide an element of the adapter or holder securely fastened to the brick and of inexpensive construction. Another object of the invention is to provide a combination of track grinding brick, a holding element permanently fastened thereto and a detachable holder so constructed that substantially all of the abrasive can be used for grinding. Another object of the invention is to provide a combination of the type indicated of Another object of the invention is to provide a combination of the type indicated permitting reuse of the holder. Another object of the invention is to provide a combination of the type indicated reducing waste of grinding material. Another object of, the invention is to provide an eflicient and practical adapter for track grinding bricks. Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts, as will be exemplified in the structure to be hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawing, in which is shown one of various possible embodiments of the mechanical features of this invention,

Fig. 1 is a fragmentary view, partly in side elevation and partly in vertical section of .a track grinder in which the adapters and bricks may be mounted for use,

Fig. 2 is a side elevation of a brick and adapter,

Fig. 3 is a vertical sectional view taken on the line 3-3 of Fig. 2.

Referring first to Fig. 1, I have therein shown a track grinder of the type illustrated and described in U. S. Letters Patent No. 1,095,994 to W. D. Gherky, and for a more complete illustration and description of the grinder than will be found herein reference may be had to that patent. Such a track grinder to which the brick and adapter of the present invention may be applied, may comprise a frame member H] which, together with a parallel frame member [0a and ways, not shown, supports a carriage H for reciprocatory movement parallel to the rail I2 to be ground, the frame l0 being supported upon the track or rail thereof by means of wheels such as the wheel l4, and there being a handle I5 1935, Serial No. 35,434

by means of which the entire apparatus may be moved along the rail l2.

The carriage II may be reciprocated in the ways referred toby means of an electric motor l6 secured to a bridge ll extending upwardly from the parallel frame members H3 and Illa, which motor 16 has a gear l8 secured to its armature shaft driving a somewhat larger gear l9 secured to a shaft which is journalled in a bracket 2! uprising from and attached to the far frame member Eta. Secured to the shaft 20 is a crank 22 which is connected by a link 23 to a lever 26 fulcrumed at 25 on a bracket 25a also uprising from and attached to the far frame member Illa. The bottom of the lever 24 is connected to a link 2% which is connected to the carriage H. Thus whenever the motor I6 is energized the carriage H is reciprocated.

Referring now to all the figures, I provide a plurality of track grinding bricks 26. The bricks may be made of any suitable abrasive material, such as aluminum oxide, silicon carbide, quartz or garnet bonded with any desired bond, for example vitrified or clay bond, sodium silicate bond, rubber, shellac or artificial resinous bond, or any variety of cement.

In shape each brick, as illustrated in Figs. 2 and 3, is a rectangular parallelopiped except that, as more clearly shown in Fig. 3, there may be a slight bevel to the bottom to correspond to the bevel of a street carrail, assuming the brick is to be used to resurface such rails. I cement an iron plate 21 to the top of the brick 26 in any suitable manner, such as by the following procedure. Sand blasting the surface of the iron plate 27 which is to be attached to the brick 26, in order to remove any rust and make the surface somewhat rough, I then clean this surface as with benzol or the like. Next I procure a mixture of rubber and sulfur for the formation, by vulcanization, of a hard rubber, the amount of sulfur being preferably at least 20% or more. I place a thin layer of such rubber having 20% or more of sulfur covering the entire area of the top of the brick 26, and then place the plate 21 1 on top of the rubber and apply substantial pressure; The brick, plate and pressure apparatus are then placed in a heating oven or the like to bring the rubber to vulcanization temperature, r which should be maintained for a number of hours. The plate 21 will be found to be firmly united to the brick 26 by attaching layer 28 of hard vulcanized rubber.

As shown in Fig. 3, the plate 21 has a bore 29 and a countersunk portion 30 in which is 10- cated a machine screw 3| having a head fitting the countersunk portion 39. This screw 3| is inserted in position prior to the bringing together of the plate 27 and brick 26 for attachment as described. Accordingly some of the rubber 28 is vulcanized to the head of the screw 3|. Preferably the head of the screw 3| should be sand blasted and cleaned with benzol at the same time that the plate 21 is so treated. As the result of the foregoing procedure the brick 26, plate 21 and screw 3| are integrally united so as to constitute, mechanically, a single piece, and in the use of the brick and grinding apparatus the abrasive of the brick 26 may be used until substantially all of the brick 26 has been worn away.

I provide a number of holding members 32 which may be used over and over again, since by means of a nut 33 they may be removably connected to plates 21, the nut 33 fitting the screw 3|. Thus in the use of a number of bricks 26 for grinding the rails practically every bit of abrasive grain constituting the bricks is used for grinding, and the only material which will usually be discarded comprises the plates 21 and screws 3|, and these need not be expensive. Thus I save considerable expense in the operation of track grinding machines of the type described.

Considering more particularly the construction of the holding members 32 and their at tachment to the plates 27, each holder comprises a fiat upper portion 35 connected by vertical portions 36 to a fiat lower portion 31 forming a hollow rectangle of iron or other suitable material. The vertical portions 36 continue downwardly in the form of legs 38 having inner surfaces 39 which are inclined to the sides of the rectangle, these surfaces being farther apart at the bottom than at the top. The plates 21 have mating surfaces 40 fitting the surfaces 39 of the legs 38, and these surfaces 40 are inset from the edges of the plate 21 so that the entire holder 32 may be included within the area between end walls 4| of the brick 26. The relative dimensions of the plate 21 between the surfaces 40 and of the holder 32 between the surfaces 39 are such that parts may be wedged together to form a tight interlock, and the nut 33 which thrusts against the lower fiat portion 31 may be tightened to clamp the parts together securely. Insomuch as often operators will excessively tighten nuts, I may provide a washer 42 between the under side of the portion 31 and the top of the plate 21 to prevent the holder 32 from being deformed by excessive pressure.

Assuming now that a number of bricks 26 have had plates 21 secured to them with screws 3| upstanding therefrom, and have been connected to holders 32 by means of nuts 33 as described, they may now be mounted in the carriage II in tandem relation, there being as shown in Fig. 1 four bricks 26 so mounted. Referring now to Fig. 1, I provide a clamping bar 43 which may be constructed as disclosed in the patent to Gherky referred to and which as therein described comprises a pair of similar halves each having complementary semi-cylindrical channels 44, which channels are positioned to receive the bolts 34 with a loose fit when the bricks 26 are arranged in tandem relation as shown in Fig. 1 and spaced by separator plates 45. The respective halves of the clamping bar 43 may be locked together by bolts 46. Between the halves of the clamping bar 43 is located a head 41 below a reduced portion 48, the head 4'I being on the lower end of a screw 49 operated by a hand wheel 50 the screw threads of which fit in a nut held by a bridge 52 whose sides 53 are connected to and uprise from the sides of the carriage H as more clearly shown in the patent to Gherky referred to. By means of the hand wheel 50 and screw 49 the bar 43 may be raised and lowered, and may be urged downwardly by the pressure of a spring 54, all as more clearly set forth in the aforesaid patent to Gherky.

The front or left-hand end of the carriage H has an inclined wall 60 and the bricks 26 extend between the vertical right-hand or rear wall of the carriage II and a vertical plate 6| Which is spaced from the inclined wall 60 by a wedge 62. By means of a screw 63 extending through a nut 64 and a bridge 65 supported by vertical members 66 extending upwardly from the carriage H, the wedge 62 may be forced downwardly, a hand wheel 61 being provided to rotate the screw 63, and this construction which is also illustrated in the patent to Gherky referred to constitutes means for holding the bricks in the carriage without excessive knocking during grinding, at the same time allowing raising and lowering of the bricks in the carriage I.

It should be understood that the description of a particular type of track grinder is illustrative merely and that the brick and adapter of the invention may be utilized in many different types of machines. The bolts 34 which have heads serve for the attachment of one or a plurality of units by any desired clamping device in the machine, and the holder or adapter may be readily removed from the clamping device. At the same time the major portion of the adapter may be used over and over again, only the plate 21 and screw 3| being in some cases discarded. The method of attachment of the plate 21 to the brick 26 forms a union substantially as strong as the brick 26 or even stronger, and nevertheless the volume of the brick used by the attaching medium is substantially zero, so that almost all of the abrasive substance may be utilized in grinding, and in fact in cases where there is no lower bevel, as shown in Fig. 3, 100% of the brick 26 may be utilized in grinding.

The parts of the adapter may be produced in quantity without great expense and owing to the attachment by screw means cooperating with a wedge the tolerances in the production of a quantity of these articles need not be extremely close as a tight union may be effected despite variations.

A particular feature of the adapters comprises the rigidity of the wedge means described and the flexibility of the connecting means. By this I mean that the surfaces 39 and 40, being formed on metal will not readily become chipped and although it is contemplated that the spacing thereof will vary in manufacturing a great quantity of bricks and adapters, nevertheless they do not vary substantially by reason of wear. On the other hand, tolerance requirements are not close because the horizontal portion 3'! can be sprung in attaching the parts together and thus a given adapter holder member 32 may fit a particular plate 2'! with the bottoms of the legs 38 just slightly below the top surface of the plate 27, and the same adapter holder member 32 may fit another plate 21 with the bottoms of the legs 38 practically in contact with the horizontal surfaces forming the base of the marginal cut-outs in the plate 21. Thus a great deal of time is saved for any holder member 32 will fit any plate 21 for which it was intended in the first place, even though a number of jigs, molds or fixtures are used in manufacturing the parts. The separator plates 45 are U-shaped, as disclosed in the patent to Gherky referred to, and are carried by the carriage, and do not prevent the bricks from being lowered until all of the abrasive substance thereof is used.

It will thus be seen that there has been provided by this invention an apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiment may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth, or shown in the accompanying drawing, is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. A track brick and adapter comprising, an abrasive brick, a metal plate secured to said brick having spaced surfaces slightly inclined to the vertical, an adapter member having a pair of spaced legs with surfaces complementary to the aforesaid surfaces, the parts with the four surfaces constituting cooperating wedge means, a horizontal integral part of the adapter member connecting said legs and so located as to leave a space between it and the plate when the parts are connected together, and a nut and bolt which together with the horizontal part form connecting means for the plate and the adapter member, the connection obviating close tolerances because of the rigidity of the wedge means and the flexibility of the connecting means.

2. A track brick and adapter comprising, an abrasive brick, a metal plate secured to said brick, an adapter member, cooperating wedge means on said plate and said adapter member, a horizontal part to said adapter member capable of being flexed, and screw means for connecting said horizontal part with said plate.

THURE LARSSON. 

